Seeds that are planted for agricultural and other purposes are often treated prior to planting. The treatments may accomplish many different purposes including deterrence or prevention of insect and other animal pests that would target sown or newly germinated seed for attack. These animals may directly cause damage to the seed or may introduce one or more pathogens, including viruses, directly into the seed. Treatments may also target bacteria, molds and fungus that have contaminated seeds or that are known to be present in the soil in which the seeds will be planted. Direct application of seed treatment allows for a reduction in the amount of treatment composition that would be required by application to soil after planting. Also, post-planting application may not penetrate the soil to a level or location where it would be effective.
Treatment of seeds, however, involves applications of chemicals and other agents that are expensive and may even be toxic to the seeds on which they are applied. The amount of treatment composition is also necessarily small and often provides protection or other advantage for only a short period of time after planting. However, in a number of situations, the advantages of treatment with one or more compositions will outweigh the disadvantages. These situations include the use of rare or expensive seed, the use of older seed or seed with low germination rates, the use of seed known to be contaminated or infested, the use of seed known to have been produced in conditions likely to lead to contamination or infestation, and the use of seed in fields known to be prone to contamination or infestation.
Various devices for treatment of seeds in batch or continuous treatment mode are known. U.S. Pat. No. 5,891,246 to Lund, the disclosure of which is hereby incorporated by reference, describes a seed coating apparatus for applying a coating fluid whereby seeds are dispersed with a seed dispersing member.
U.S. Pat. No. 4,657,773 to Mueller, the disclosure of which is hereby incorporated by reference, describes a process and apparatus for dressing seed in which seed is guided over a dispensing cone through a jet of dressing and onto a rotary table.
DE 4411058 to Niklas, the disclosure of which is hereby incorporated by reference, describes a device with a mixing bowl connected to a high speed, multi-turn actuator and a mechanism to feed seed into the mixing bowl. The bowl rotates to rotate seed being treated therein. The seed treating formulation is sprayed in the bowl while the seed is being rotated to uniformly coat the seed with the formulation.